Prior to reading this document, please familiarise yourself with the following documents Single-Phase Eastron Meter with Single-Phase Inverter or 3 Phase Eastron Meter with 3 Phase Inverter (depending on your inverter type), Recommended External Meters and Eastron Meters: CT Selection and Settings to ensure that you have the correct meter.
W04 Meter Comm fail indicates there an issue with the communication between the inverter and your external meter. To troubleshoot this issue:
1. Check that you have the correct Eastron Meter for you system by checking the compatibility guide above - Recommended External Meters. Meters not included in this document have NOT been tested and we cannot guarantee compatibility.
2. Check the meter is reading correctly. To do this power off the inverter and check the display of your Eastron Meter. With the inverter switched off the meter display should display the current household demand. This value should be POSITIVE.
(If this is not the default page use the Eastron meter buttons to scroll to the page showing W or kW.)
3. Check you communications cable is using the correct pins for RS485 communications based on your inverter. These are below:
Pin | 1P 3.6/5.5kW Ecco | 1P 8kW Ecco | 1P 10/12/16kW | 3P 8/10/12/25/50kW |
1 | 485-B |
| 485-B | 485-A |
2 | 485-A |
| 485-A | 485-B |
3 |
|
|
|
|
4 | 485-B | 485-B |
| 485-B |
5 | 485-A | 485-A |
| 485-A |
6 |
|
|
|
|
7 | 485-A |
| 485-A | 485-A |
8 | 485-B |
| 485-B | 485-B |
4. Check you have Ex_Meter for CT enabled and the correct meter type in the inverter settings:
As single-phase inverters work with both single-phase a three-phase meters the meter select will have Eastron 1P or Eastron 3P as options, please make sure you set this per the meter type.
5. Check your inverter has the correct firmware version. 3.6/5/8kW inverters manufactured in 2024 and all 10/12/16kW single-phase units require a firmware patch to allow meter communications.
6. In some cases there can be a lot of interference on the line. If persistent W04 alarms occur after checking the above, tap off a smaller supply to the meter close to the inverter and run a short comms cable just to check communications can be established. If communications are successful in this case then there is interference on the line preventing correct communications. Some things that can reduce interference include:
- Upgrading the communications cable to a shielded cable.
- Making sure the cable is not installed alongside the AC cabling.
- Installing a 120Ω resistor between 485-A and 485-B.
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